Films having a high transmittance and matt property

ABSTRACT

A film having a high transmittance and matt property is disclosed which has, on a transparent support  1 , a hard coat layer  2  incorporated therein particles  4  of a particle size of 1.0 to 10 μm that is larger than the layer thickness thereof, and a low-refractive-index layer  3  having a refractive index of 1.45 or less and covering said hard coat layer, wherein a haze value is 1.0% or more, and a total transmittance of light is 93.5% or more. The film having a high transmittance can prevent occurrence of unevenness of display due to thermal expansion of a light-tuning film and occurrence of unevenness of brightness peculiar to the light-tuning film.

This application is a 371 of PCT/JP00/00622 filed Feb. 4, 2000.

TECHNICAL FIELD

The present invention relates to a film having a high transmittance andmatt property, a polarizing plate, and an image display device using thesame as a component member thereof.

BACKGROUND ART

An example of the construction of a conventional liquid crystal displaydevice is shown in FIG. 2. FIG. 2 shows a diagrammatic side view of anordinary liquid crystal display device that is composed of, as shown inthe figure, a backlight 11 of an edge light type on the furthest backsurface and, in the order from the furthest back surface, a lightintroductive plate 12 for injecting light from the back light toward thesurface, a scattering sheet 13 for uniformly dispersing brightness ofthe light, and one or plural light-tuning sheet (light tuning film) 14having a function for condensing the uniformly dispersed light by thescattering sheet to a given direction or alternatively a function forselectively transmitting or reflecting a specific polarized light. Lightpassing through these films is injected to a liquid crystal cell 17interposed between a pair of polarizing plates 15 and 16. In the figure,18 denotes a cooled cathode fluorescent tube as light source and 19 areflective sheet.

In the liquid crystal display device, usually the light tuning film 14and the backside polarizing plate 15 located on the side of the liquidcrystal cell are especially not bonded with a binder or the like so thata slight gap exists between both. This light tuning film 14 is made ofan acrylic resin, a polyester, a polycarbonate or the like, but thesematerials are rather larger in stretching or shrinking caused by changein temperature so that the light tuning film 14 elongated by heating dueto ambient circumstance, backlight or the like is brought into contactwith the backside polarizing plate 15 to cause non-uniformity in displayin circumferential areas of image. In some of the light tuning films,there exists a unique brightness non-uniformity, thus bringing aboutdeterioration in their display quality. With regard to theabove-mentioned light-tuning film, JP-A-10-240143 (“JP-A” meansunexamined published Japanese patent application) describes that anirregularity (concavo-convex structure) that is formed by transparentparticles on the surface of the light-tuning film prevents deteriorationof the display quality when dew condensation occurs in the gap between alight-tuning film and a backside polarizing plate, and consequently theyadsorb each other via dew droplets.

However, the polarizing plate still fails to prevent unevenness of thedisplay that occurs when the polarizing plate contacts a light-tuningfilm due to thermal expansion, and unevenness of the brightness that ispeculiar to the light-tuning film. Further, the polarizing plate has adisadvantage of reducing transmittance of the back light. To preventunevenness of the brightness of the light-tuning film, it isconventionally proposed to use another scattering film between thelight-tuning film and a liquid crystal cell. Generally, however, sincethe scattering film has a haze, the transmittance tends to be lowered.Accordingly, it is difficult to avoid the possibility that reduction inbrightness of the display may be caused by giving matt property thereto.

Accordingly, an object of the present invention is to provide a filmhaving a high transmittance that is able to prevent occurrence of bothunevenness of the display due to thermal expansion of the light-tuningfilm, and unevenness of the brightness that is peculiar to thelight-tuning film, as mentioned above. Another object of the presentinvention is to provide a polarizing plate using a film having a hightransmittance that has improved such existing disadvantages. Stillanother object of the present invention is to provide a liquid crystaldisplay device to which a stable high quality of display is given byusing the film having a high transmittance or the polarizing plate.

Other and further objects, features, and advantages of the inventionwill appear more fully from the following description, taken inconnection with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional view schematically illustrating the layerconstitution of a film having a high transmittance and matt property.

FIG. 2 is a side view diagrammatically showing an example of aconventional liquid crystal display device.

DISCLOSURE OF THE INVENTION

The objects of the present invention have been attained by the followingmeans.

(1) A film having a high transmittance and matt property, comprising, ona transparent support, a hard coat layer incorporated therein particlesof a particle size of 1.0 to 10 μm that is larger than the thickness ofthe hard coat layer, and a low-refractive-index layer having arefractive index of 1.45 or less and covering said hard coat layer,wherein the film has a haze value of 1.0% or more, and a totaltransmittance of light of 93.5% or more.(2) The film having a high transmittance and matt property according tothe above (1), wherein said low-refractive-index layer is formed byincorporating therein a fluorine-containing macromolecular compoundbeing cross-linked by heat or ionization radiation, and has acoefficient of kinetic friction of 0.2 or less.(3) The film having a high transmittance and matt property according tothe above (1), wherein said hard coat layer contains a cross-linkedbinder polymer, and monodispersed transparent fine particles having anaverage particle size larger than the average thickness of the hard coatlayer and having a particle size distribution of 0.2 or less in terms ofcoefficient of variation.(4) The film having a high transmittance and matt property according tothe above (1), wherein said hard coat layer contains a cross-linkedbinder polymer, and monodispersed transparent fine particles composed ofa resin having a Moh's scale of hardness of less than 7, which have anaverage particle size larger than the average thickness of the hard coatlayer and which have a particle size distribution of 0.2 or less interms of coefficient of variation, and wherein said low-refractive-indexlayer is composed of a fluorine-containing compound being cross-linkedwith a refractive index of 1.45 or less and a coefficient of kineticfriction of 0.15 or less.(5) The film having a high transmittance and matt property according tothe above (3), wherein the low-refractive-index layer is formed byincorporating therein a fluorine-containing macromolecular compoundbeing cross-linked by heat or ionization radiation, and has acoefficient of kinetic friction of 0.2 or less.(6) The film having a high transmittance and matt property according tothe above (5), wherein said hard coat layer contains a cross-linkedbinder polymer, and monodispersed transparent fine particles composed ofa resin having a Moh's scale of hardness of less than 7, which have anaverage particle size larger than the average thickness of the hard coatlayer and which have a particle size distribution of 0.2 or less interms of coefficient of variation, and wherein said low-refractive-indexlayer is composed of a fluorine-containing compound being cross-linkedwith a refractive index of 1.45 or less and a coefficient of kineticfriction of 0.15 or less.(7) The film having a high transmittance and matt property according tothe above (1), wherein said film having a high transmittance and mattproperty is an optical film comprising, on a transparent support, a hardcoat layer and a low-refractive-index layer having a lower refractiveindex than that of said transparent support, laminated in this order,and wherein said hard coat layer contains a cross-linked binder polymer,and monodispersed transparent fine particles having an average particlesize larger than the average thickness of the hard coat layer and havinga particle size distribution of 0.1 or less in terms of coefficient ofvariation.(8) A polarizing plate having a high transmittance and matt property,comprising a polarizing layer and two protective films thereon, whereinat least one of the protective films is the film having a hightransmittance and matt property according to any one of the above (1) to(7), and wherein a matted layer is disposed at the opposite side to thepolarizing layer.(9) A liquid crystal display device, using the film having a hightransmittance and matt property according to any one of the above (1) to(7).(10) A liquid crystal display device, comprising two polarizing platesprovided on both sides of a liquid crystal cell, wherein the polarizingplate provided at the backlight side is the polarizing plate having ahigh transmittance and matt property according to the above (8), thematted layer being disposed toward the backlight side.

By the term “matt property” referred to herein is meant a performancethat a concavo-convex structure is formed on the surface andnon-uniformity due to interference is not generated when brought intocontact with a smooth surface. Haze rate is preferably 1.0 to 10.0%,more preferably 2.0 to 6.0%.

BEST MODE FOR CARRYING OUT THE INVENTION

Preferable embodiments of the film having a high transmittance and mattproperty of the present invention, and the polarizing plate or theliquid crystal display device using the same, are explained below withreference to figures, as the occasion may demands.

FIG. 1 is a schematic cross sectional view showing the layerconstruction of the film having a high transmittance and matt property.The film having a high transmittance and matt property has a layerconstruction in the written order of a transparent support 1, a hardcoat layer 2 and a layer having a low refractive index 3. The hard coatlayer contains particles 4 having a particle diameter of 1.0 to 10 μm,which particles form a concavo-convex structure on the surface andimpart haze to the film. The particles 4 in the hardcoat layer has aparticle diameter preferably 1.0 to 10 μm, more preferably 3 to 10 μm.For a low-refractive-index layer, generally use can be made of afluorine-containing resin film, a sol-gel film, a laminated film of fineparticles having a particle diameter of 200 nm or less, avapor-deposited silicon dioxide film, each having a refractive index of1.45 or less, preferably 1.40 or less. The refractive index and filmthickness of the layer is preferably to satisfy the following formula(I):mλ/4×0.7<n ₁ d ₁ <mλ/4×1.3  (I)wherein m is a positive odd number (generally 1), λ represents awavelength of light, n₁ represents a refractive index of thelow-refractive-index layer, and d₁ represents a film thickness (nm) ofthe low-refractive-index layer.

As is apparent from FIG. 1, the particle 4 is preferably larger inparticle diameter than the layer thickness of the hard coat layer 2.

It is preferable to use a plastic film as the transparent support.Examples of materials for the plastic film include a cellulose ester(for example, triacetyl cellulose, diacetyl cellulose, propionylcellulose, butyryl cellulose, acetyl propionyl cellulose andnitrocellulose), a polyamide, a polycarbonate, a polyester (for example,polyethylene terephthalate, polyethylene naphthalate,poly-1,4-cyclohexanedimethylene terephthalate,polyethylene-1,2-diphenoxyethane-4,4′-dicarboxylate and polybutyleneterephthalate), a polystyrene (for example, syndiotactic polystyrene), apolyolefin (for example, polypropylene, polyethylene orpolymethylpentene), a polysulfone, a polyethersulfone, a polyarylate, apolyether imide, a polymethyl methacrylate, and a polyether ketone. Itis preferable to use triacetyl cellulose, a polycarbonate andpolyethylene terephthalate. The transparent support preferably has alight transmittance of 80% or more, more preferably 86% or more. Haze ofthe transparent support is preferably 2.0% or less, more preferably 1.0%or less. A refractive index of the transparent support is preferably1.40 to 1.70.

It is preferable to use a polymer having a saturated hydrocarbon orpolyether as a main chain thereof as a compound for use in the hard coatlayer. More preferable is a polymer having a saturated hydrocarbon as amain chain. The polymeric binder (binder polymer) is preferablycrosslinked. The polymer having a saturated hydrocarbon as a main chainthereof is preferably obtained by polymerization reaction of anethylenically unsaturated monomer. For obtaining a crosslinked polymericbinder, it is preferable to use a monomer having at least twoethylenically unsaturated groups.

Examples of the monomer having at least two ethylenically unsaturatedgroups include an ester of a polyhydric alcohol and (meth)acrylic acid(for example, ethyleneglycol di(meth)acrylate, 1,4-cyclohexanedioldiacrylate, pentaerithritol tetra(meth)acrylate), pentaerithritoltri(meth)acrylate, trimethylolpropane tri(meth)acrylate,trimethylolethane tri(meth)acrylate, dipentaerithritoltetra(meth)acrylate, dipentaerithritol penta(meth)acrylate,pentaerithritol hexa(meth)acrylate, 1,2,3-cyclohexane tetramethacrylate,polyurethane polyacrylate and polyester polyacrylate), vinylbenzene anda derivative thereof (for example, 1,4-divinylbenzene, 4-vinylbenzoicacid-2-acryloylethyl ester, and 1,4-divinylcyclohexanone), avinylsulfone (for example, divinylsulfone), and an acrylamide (forexample, methylene-bis-acrylamide) and a methacrylamide.

A polymer containing a polyether as a main chain thereof is preferablysynthesized by ring-opening polymerization of a polyfunctional epoxycompound.

These monomers having ethylenically usaturated groups have to be curedby polymerization due to ionizing radiation or heat after applicationonto the film.

In place of or in addition to the monomer having at least twoethylenically unsaturated groups, a crosslinked structure may beintroduced into the polymeric binder by the reaction of a crosslinkablegroup. Examples of the crosslinkable functional group include isocyanategroup, epoxy group, aziridine group, oxazoline group, aldehyde group,carbonyl group, hydrazine group, carboxyl group, methylol group, andactive methylene group. Vinylsulfonic acid, an acid anhydride, acyanoacrylate derivative, melamine, etherified methylol, an ester, aurethane and a metal alkoxide such as tetramethoxysilane can also beutilized as a monomer for introducing a crosslinking structure. Afunctional group exhibiting crosslinking property as a result of adecomposition reaction such as a blocked isocyanate group may also beused. The term “crosslinkable group” referred to herein means a groupexhibiting reactivity as a result of decomposition of the functionalgroup mentioned above and is not limited to the aforesaid compounds.

Compounds having such a crosslinkable group have to be crosslinked byheat or the like after applied onto a film.

Examples of the matt particles to be incorporated into the hard coatlayer include fine particles of inorganic substances such as silicondioxide, titanium dioxide, magnesium oxide, calcium carbonate, magnesiumcarbonate, barium sulfate, and strontium sulfate, and fine particles oforganic substances such as poly(methyl acrylate), poly(methylmethacrylate), polyacrylonitrile, polystyrene, cellulose acetate,cellulose acetate propionate. Among them, preferred are silicon dioxideas the inorganic substance, while polymethyl methacrylate as the organicsubstance.

The matt particles to be incorporated into the hardcoat layer arepreferably composed of a resin having a Moh's hardness of less than 7.Examples of the resin include poly(methyl methacrylate) resins,fluororesins, vinylidene fluoride resins, silicone resins, epoxy resins,nylon resins, polystyrene resins, phenol resins, polyurethane resins,crosslinked acrylic resins, crosslinked polystyrene resins. The mattparticles are preferably insoluble in water and organic solvents.

The matt particles preferably have a size of an average particlediameter of 1 to 10 μm, more preferably 3 to 10 μm, and especiallypreferably 3 to 7 μm. A particle diameter distribution of the particleshas preferably a variation coefficient of 0.2 or less, and the particleshaving a high monodispersibility and a variation coefficient of 0.1 orless are especially preferable. When the coefficient of variation is solarge that the particle size distribution is too wide, sometimes mattproperty is not enough.

By the term “variation coefficient” referred to herein is defined avalue obtained according to the following formula (II):

$\begin{matrix}{\sqrt{\frac{\sum{\left( {\overset{\_}{r} - {ri}} \right)^{2} \cdot {ni}}}{\sum{ni}}} \div \overset{\_}{r}} & ({II})\end{matrix}$wherein {overscore (r)} represents a number average particle diameter,ni represents a particle of ordinal i number, and ri represents theparticle diameter of a particle of ordinal i number.

In case the particles of matt property are to be incorporated into thehard coat layer, it is preferable to use a combination of an averageparticle diameter of the particles of matt property being larger by 0.5to 5.0 μm than the thickness of the hard coat layer. Especiallypreferable combination is an average particle diameter larger by 1 to 3μm than the thickness.

As the fine particles to be incorporated into the hard coat layer, twoor more of the particles may be used in combination to adjust haze. Theparticles equal to or smaller than the thickness of the hard coat layerare not included in the particles of matt property.

The density of the coated particles of matt property depends on thedegree of haze, but preferably it is within the range of 100 to 5000particles/m², more preferably 200 to 2000 particles/m².

Further, the hard coat layer may be incorporated with inorganic fineparticles with a purpose of adjusting the refractive index and enhancingcured hardness of the film. Inorganic fine particles have preferably anaverage particle size of 0.5 μm or less, and especially preferably 0.2μm or less.

Examples of the inorganic fine particles include silicon dioxideparticles, titanium dioxide particles, aluminum oxide particles, tinoxide particles, calcium carbonate particles, barium sulfate particles,talc, kaolin and calcium sulfate particles. Especially preferable aresilicon dioxide particles, titanium dioxide particles and aluminum oxideparticles.

An amount of the inorganic fine particles to be incorporated ispreferably 10 to 90% by weight, more preferably 20 to 80% by weight, andespecially preferably 30 to 60% by weight of the total mass of the hardcoat layer.

A thickness of the hard coat layer is preferably 0.5 to 15 μm, morepreferably 1 to 10 μm, and furthermore preferably 1 to 8 μm.

Examples of the compound which can be used to form thelow-refractive-index layer include fluorine-containing macromolecularcompounds and silicon compounds substituted with an organic substituent,represented by the general formula shown below. Among them,fluorine-containing compounds are preferred. Particularly preferred arefluorine-containing macromolecular compounds which can be cross-linkedby heat or ionization radiation. Among them, especially preferably usedare fluorine-containing compounds which have a refractive index of 1.45or less, more preferably a lower refractive index than that of thetransparent support used, further more preferably 1.42 or less, and alsohave a coefficient of kinetic friction of 0.15 or less, and which can becross-linked by heat or ionization radiation. To regulate coatingproperty, a degree of film hardening and the like, they may be used withanother compound in combination. Examples of the cross-linkablefluorine-containing compound include fluorine-containing monomers andcross-linkable fluorine-containing polymers. Among them, it ispreferable from the viewpoint of coating property to use thecross-linkable fluorine-containing polymers.

Examples of these cross-linkable fluorine-containing macromolecularcompound include perfluoroalkyl group-containing silane compounds (forexample, (heptadecafluoro-1,1,2,2-tetradecyl)triethoxysilane), as wellas fluorine-containing copolymers composed of a fluorine-containingmonomer and another monomer for providing a cross-linkable group, asconstitutional units.

Specific examples of the fluorine-containing monomer unit include, forexample, fluoroolefins (for example, fluoroethylene, vinylidenefluoride, tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene,perfluoro-2,2-dimethyl-1,3-dioxole, etc.), a partially or completelyfluorinated alkyl ester derivative of (meth)acrylic acid (for example,Biscoat 6FM (trade name, manufactured by Osaka Yukikagaku KK) and M-2020(trade name, manufactured by Daikin KK)), and a partially or completelyfluorinated vinyl ethers.

Examples of the monomer imparting a crosslinkable group include, inaddition to a (meth)acrylate monomer having previously a cross-liningfunction in the molecule thereof such as glycidyl methacrylate, a(meth)acrylate monomer having carboxyl group, hydroxyl group, aminogroup or sulfonic acid group (for example, (meth)acrylic acid, methylol(meth)acrylate, hydroxyalkyl (meth)acrylate, allyl acrylate, etc.). Thelatter mentioned monomer is known in JP-A-10-25388 and JP-A-10-147739 asa monomer capable of introducing a crosslinking structure aftercopolymerization. Compounds other than these may additionally be used.

An example is a compound represented by the following formula or ahydrolysis product thereof:R¹ _(a)R² _(b)SiX_(4−(a+b))wherein R¹ and R² each represent an alkyl group, an alkenyl group, anaryl group, or a hydrocarbon group having a halogen atom, an epoxygroup, an amino group, a mercapto group, a methacryloxy group or a cyanogroup, X represents a hydrolysable substituent selected from an alkoxylgroup, an alkoxyalkoxyl group, a halogen atom or an acyloxy group, a andb each are 0, 1 or 2 and a+b is 1 or 2.

As disclosed in JP-A-9-288201, a low-refractive-index layer can beformed by homogeneously containing aerial or vacuum microvoids having asize equal to or smaller than wavelength of light in the layer.

It is preferable for providing scratch resistance that thelow-refractive-index layer has a coefficient of kinetic friction of 0.20or less. If the coefficient of kinetic friction is too large, theperformance of scratch resistance is inferior, because hardness is low.For example, at the time when a film is processed to form a polarizingplate, sometimes scratch occurs, which may result in unevenness ofdisplay.

Examples of the fluorine-containing macromolecular compound for use inthe low-refractive-index layer include polymers which are formed bypolymerizing a fluorine-containing monomer. Specific examples of thesemonomer unites include fluoro olefins (e.g., fluoroethylene,vinylidenefluoride, tetrafluoroethylene, hexafluoroethylene,hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxonol), partially orcompletely fluorinated alkyl ester derivatives of (meth)acrylic acid,and partially or completely fluorinated vinyl ethers. Among these, onemonomer or a plurality of monomers are selected and combined with eachother in an optional proportion for copolymerization. In this way,desired polymers can be obtained.

Further, not only polymers of the above-described fluorine-containingmonomers as a constitutional unit, but also other copolymers of theabove-described fluorine-containing monomers and fluorine-free monomers,may be used. No particular limitation exists in utilizable monomerunits. For example, mention can be made of olefins (e.g. ethylene,propylene, isoprene, vinyl chloride, vinylidene chloride), esters ofacrylic acid (methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate),esters of methacrylic acid (e.g. methyl methacrylate, ethylmethacrylate, butyl methacrylate, ethylene glycol dimethacrylate),styrene derivatives (e.g. styrene, divinylbenzene, vinyltoluene,α-methylstyrene), vinyl ethers (e.g. methyl vinyl ether), vinyl esters(e.g. vinyl acetate, vinyl propionate, vinyl cinnamate), acrylamides(e.g. N-tert-butylacrylamide, N-cyclohexylacrylamide), methacrylamidesand acrylonitrile derivatives.

The refractive index of the low-refractive-index layer is 1.45 or less,which is lower than that of a transparent support. Further, it ispreferable that the refractive index of the low-refractive-index layeris lower than that of the substrate which is used to be coated by thelow-refractive-index layer thereon. The refractive index can be measuredby the following method.

(Measurement of Refractive Index)

The refractive index of the low-refractive-index layer after hardening,is determined by the following steps:

On a polyethylene terephthalate film exhibiting the refractive index of1.66, a low-refractive-index layer having a thickness of 0.1 μm isformed and hardened. Then, a spectral refrectance of the formedlow-refractive-index layer at an incidence of 5° in the range of 380 nmto 780 nm is measured by means of a spectrophotometer. The refractiveindex is determined by the minimum value of the obtained reflectances.

Each layer of the film having a high transmittance and matt property canbe formed by applying the materials according to the dip coating method,the air-knife coating method, the curtain coating method, the rollercoating method, the wire bar coating method, the gravure coating methodand the extrusion coat method (U.S. Pat. No. 2,681,294). Two or morelayers may be coated at the same time. A means for coating layers at thesame time is disclosed in U.S. Pat. Nos. 2,761,791, 2,941,898, 3,508,947and 3,526,528 and a Japanese book entitled “Kotingu Kogaku (CoatingTechnology)” written by Yuji Harazaki, p. 253, published by AsakuraShoten (1973).

The film having a high transmittance and matt property of the presentinvention can be used in a liquid crystal display device. However, theliquid crystal display device is not limited to one shown in theforegoing FIG. 2. The film of the present invention can also be used inliquid crystal display devices of various other embodiments. The liquidcrystal display device of the present invention may be, for example, anembodiment in which the layer of the film having a high transmittanceand matt property of the present invention is formed with the liquidcrystal display device in one united body.

It is preferable that the film having a high transmittance and mattproperty is adhered to a polarizing plate by means of an adhesive sothat the transparent support side of the film contacts with thepolarizing plate, or alternatively the film having a high transmittanceand matt property is used as at least one of two protective films for apolarizing layer of the polarizing plate so that a matted layer isdisposed at the side opposite to the polarizing layer. In the liquidcrystal display device, such a polarizing plate having a hightransmittance and matt property can be generally used as a back lightside polarizing plate among two polarizing plates which are disposed atboth sides of a liquid crystal cell, and the above-mentioned mattedlayer is disposed toward the back light side

The films having matt property of the present invention according toclaims 1 to 7 are of high transmittance and can be used in thepolarizing plate of a liquid crystal display device, thereby occurrenceof both unevenness of display due to thermal expansion of thelight-tuning film and unevenness of brightness can be prevented.Further, the films having a high transmittance of the present inventionare excellent in scratch resistance in addition to the above-mentionedcharacteristics, and therefore they provide the advantage that noscratch occurs on the light-tuning film.

Further, the polarizing plate having matt property of the presentinvention according to claim 8 has high brightness, and it is excellentin scratch resistance in addition to the above-mentionedcharacteristics, and therefore they exhibit the advantage that noscratch occurs on the light-tuning film.

Accordingly, the liquid crystal display device according to claim 9 or10 provides a stable high quality of display.

The present invention will be explained in more detail by way of thefollowing examples, but the present invention is not limited to theseexamples.

EXAMPLES

(Preparation of a Coating Solution A for a Hard Coat Layer)

In a mixed solvent of 78.8 g of isopropanol, 157.2 g of methyl isobutylketone and 102.1 g of methanol was dissolved 256.5 g of a mixture ofdipentaerythritol pentaacrylate and dipentaerithritol hexaacrylate (DPHA(trade name, manufactured by Nihon Kayaku KK)). To the resultantsolution was added 5.4 g of a photopolymerization initiator (Irgacure907 (trade name, manufactured by Ciba-Geigy Co.)). The resultant mixturewas stirred to dissolve the initiator, and it was filtered through afilter made of polypropylene having a pore diameter of 1 μm. Further, tothe filtrate, was added 1.3 g of cross-linking acrylic particles havingan average particle size of 5.0 μm and a coefficient of variation of 0.1(MX-500H, trade name, manufactured by Soken Chemical & Engineering Co.,Ltd.), and it was stirred, to prepare a coating solution A for a hardcoat layer.

(Preparation of a Coating Solution B for a Hard Coat Layer)

To a mixed solvent of 673.3 g of isopropanol and 146.7 g of methylisobutyl ketone, a UV-cross-linkable hard coat material (KZ-7874, tradename, manufactured by JSR KK) was added. The resultant mixture wasstirred and then it was filtered through a polypropylene filter having apore diameter of 1 μm. Further, to the filtrate 1.3 g of cross-linkingacrylic particles having an average particle size of 5.0 μm and acoefficient of variation of 0.1 (MX-500H, trade name, manufactured bySoken Chemical & Engineering Co., Ltd.) and 1.3 g of cross-likingacrylic particles having an average particle size of 3.0 μm and acoefficient of variation of 0.1 (MX-300H, trade name, manufactured bySoken Chemical & Engineering Co., Ltd.) were added, and they werestirred, to prepare a coating solution B for a hard coat layer.

(Preparation of a Coating Solution C for a Hard Coat Layer)

In a mixed solvent of 78.8 g of isopropanol, 157.2 g of methyl isobutylketone and 102.1 g of methanol, was dissolved 256.5 g of a mixture ofdipentaerythritol pentaacrylate and dipentaerithritol hexaacrylate(DPHA, manufactured by Nihon Kayaku KK). To the resultant solution wasadded 5.4 g of a photopolymerization initiator (Irgacure 907,manufactured by Ciba-Geigy Co.). The resultant mixture was stirred todissolve the initiator, and it was filtered through a filter made ofpolypropylene having a pore diameter of 1 μm. Further, to the filtrate,2.6 g of polydispersed melamine-resin particles having an averageparticle size of 3.0 μm (Epostar MS, trade name, manufactured by NihonShokubai KK) was added, and it was stirred, to prepare a coatingsolution C for a hard coat layer.

(Preparation of a Coating Solution D for a Hard Coat Layer)

In a mixed solvent of 127.2 g of isopropanol and 210.9 g of methanol,was dissolved 256.5 g of a urethane acrylate oligomer (UV-6300B, tradename, manufactured by Nihon Gosei Kagaku KK). To the resultant solution,was added 5.4 g of a photopolymerization initiator (Irgacure 907,manufactured by Ciba-Geigy Co.). The resultant mixture was stirred todissolve the initiator, and it was filtered through a filter made ofpolypropylene having a pore diameter of 1 μm. Further, to the filtrate,1.3 g of cross-linking styrene particles having an average particle sizeof 5.0 μm and a coefficient of variation of 0.1 (SX-507H, trade name,manufactured by Soken Chemical & Engineering Co., Ltd.) was added, andit was stirred, to prepare a coating solution D for a hard coat layer.

(Preparation of a Coating Solution E for a Hard Coat Layer)

In a mixed solvent of 78.8 g of isopropanol, 157.2 g of methyl isobutylketone and 102.1 g of methanol, was dissolved 256.5 g of a mixture ofdipentaerythritol pentaacrylate and dipentaerithritol hexaacrylate(DPHA, manufactured by Nihon Kayaku KK). To the resultant solution wasadded 5.4 g of a photopolymerization initiator (Irgacure 907,manufactured by Ciba-Geigy Co.). The reluctant mixture was stirred todissolve the initiator, and it was filtered through a filter made ofpolypropylene having a pore diameter of 1 μm, to prepare a coatingsolution E for a hard coat layer.

(Preparation of a Coating Solution F for a Hard Coat Layer)

In a mixed solvent of 78.8 g of isopropanol, 157.2 g of methyl isobutylketone and 102.1 g of methanol, was dissolved 256.5 g of a mixture ofdipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate(DPHA, manufactured by Nihon Kayaku KK). To the resultant solution wasadded 5.4 g of a photopolymerization initiator (Irgacure 907,manufactured by Ciba-Geigy Co.). The resultant mixture was stirred todissolve the initiator, and it was filtered through a filter made ofpolypropylene having a pore diameter of 1 μm. Further, to the filtratewas added 10.0 g of silica particles (Siho-star KE-P50, trade name,manufactured by Nihon Shokubai KK) having an average particle diameterof 0.5 μm, and then it was stirred, to prepare a coating solution F fora hard coat layer.

(Preparation of a Coating Solution G for a Hard Coat Layer)

In a mixed solvent of 78.8 g of isopropanol, 157.2 g of methyl isobutylketone and 102.1 g of methanol, was dissolved 256.5 g of a mixture ofdipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate(DPHA, manufactured by Nihon Kayaku KK). To the resultant solution wasadded 5.4 g of a photopolymerization initiator (Irgacure 907,manufactured by Ciba-Geigy Co.). The resultant mixture was stirred todissolve the initiator, and it was filtered through a filter made ofpolypropylene having a pore diameter of 1 μm. Further, to the filtratewas added 10 g of amorphous silica particles (Mizukasil P-526: tradename, manufactured by Mizusawa Kagaku KK) having an average particlediameter of 3 μm, and then it was stirred and dispersed by high-speeddisperser at 5000 rpm for 1 hour, and it was filtered through a filtermade of polypropylene having a pore diameter of 30 μm, to prepare acoating solution G for a hard coat layer.

(Preparation of a Coating Solution H for a Hard Coat Layer)

In a mixed solvent of 78.8 g of isopropanol, 157.2 g of methyl isobutylketone and 102.1 g of methanol, was dissolved 256.5 g of a mixture ofdipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate(DPHA, manufactured by Nihon Kayaku KK). To the resultant solution wasadded 5.4 g of a photopolymerization initiator (Irgacure 907,manufactured by Ciba-Geigy Co.). The resultant mixture was stirred todissolve the initiator, and it was filtered through a filter made ofpolypropylene having a pore diameter of 1 μm. Further, to the filtratewas added 20.0 g of silica particles (Siho-star KE-P150, manufactured byNihon Shokubai KK) having an average particle diameter of 1.5 μm, andthen it was stirred, to prepare a coating solution H for a hard coatlayer.

(Preparation of a Coating Solution A for a Low-Refractive-Index Layer)

To 200 g of a thermo-cross-linkable fluorine-containing polymer(JN-7219, trade name, manufactured by JSR KK) was added 200 g of methylisobutyl ketone. The resultant mixture was stirred, and it was filteredthrough a filter made of polypropylene having a pore diameter of 1 μm,to prepare a coating solution for a low-refractive-index layer.

Example 1

The aforesaid coating solution C for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, trade name, manufactured by FujiPhoto Film Co., Ltd.) having a thickness of 80 μm, using a bar coater,and the resultant film was dried at 120° C. and then irradiated withUV-rays at an irradiation dose of 300 mJ/cm² and an illuminance of 400mW/cm², using a 160 W/cm air-cooled metal halide lamp (manufactured byAi Graphics KK), to cure the coated layer, to form a hard coat layerhaving a thickness of 2 μm.

Then, the aforesaid coating solution A for a low-refractive-index layerwas coated onto the hard coat layer, using a bar coater, and it wasdried at 80° C. and heated at 120° C. for 10 minutes to effect thermalcrosslinking, to form a low-refractive-index layer having a thickness of0.096 μm.

Example 2

The aforesaid coating solution D for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co.,Ltd.) having a thickness of 80 μm, using a bar coater, and the resultantfilm was dried at 120° C. and then irradiated with UV-rays at anirradiation dose of 300 mJ/cm² and an illuminance of 400 mW/cm², using a160 W/cm air-cooled metal halide lamp (manufactured by Ai Graphics KK),to cure the coated layer to form a hard coat layer having a thickness of3 μm.

Then, the aforesaid coating solution A for a low-refractive-index layerwas coated onto the hard coat layer, using a bar coater, and it wasdried at 80° C. and heated at 120° C. for 10 minutes to effect thermalcrosslinking, to form a low-refractive-index layer having a thickness of0.096 μm.

Comparative Example 1

The aforesaid coating solution A for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co.,Ltd.) having a thickness of 80 μm, using a bar coater, and the resultantfilm was dried at 120° C. and then irradiated with UV-rays at anirradiation dose of 300 mJ/cm² and an illuminance of 400 mW/cm², using a160 W/cm air-cooled metal halide lamp (manufactured by Ai Graphics KK),to cure the coated layer to form a hard coat layer having a thickness of3 μm.

Comparative Example 2

The aforesaid coating solution B for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co.,Ltd.) having a thickness of 80 μm, using a bar coater, and the resultantfilm was dried at 120° C. and then irradiated with UV-rays at anirradiation dose of 300 mJ/cm² and an illuminance of 400 mW/cm², using a160 W/cm air-cooled metal halide lamp (manufactured by Ai Graphics KK),to cure the coated layer to form a hard coat layer having a thickness of3 μm.

Comparative Example 3

The aforesaid coating solution E for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co.,Ltd.) having a thickness of 80 μm, using a bar coater, and the resultantfilm was dried at 120° C. and then irradiated with UV-rays at anirradiation dose of 300 mJ/cm² and an illuminance of 400 mW/cm², using a160 W/cm air-cooled metal halide lamp (manufactured by Ai Graphics KK),to cure the coated layer by cross-linking, to form a hard coat layerhaving a thickness of 3 μm.

Comparative Example 4

The aforesaid coating liquid E for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co.,Ltd.) having a thickness of 80 μm, using a bar coater, and the resultantfilm was dried at 120° C. and then irradiated with UV-rays at anirradiation dose of 300 mJ/cm² and an illuminance of 400 mW/cm², using a160 W/cm air-cooled metal halide lamp (manufactured by Ai Graphics KK),to cure the coated layer to form a hard coat layer having a thickness of3 μm.

Then, the aforesaid coating solution A for a low-refractive-index layerwas coated onto the hard coat layer, using a bar coater, and it wasdried at 80° C. and heated at 120° C. for 10 minutes to effect thermalcrosslinking, to form a low-refractive-index layer having a thickness of0.096 μm.

Comparative Example 5

The aforesaid coating solution F for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co.,Ltd.) having a thickness of 80 μm, using a bar coater, and the resultantfilm was dried at 120° C. and then irradiated with UV-rays at anirradiation dose of 300 mJ/cm² and an illuminance of 400 mW/cm², using a160 W/cm air-cooled metal halide lamp (manufactured by Ai Graphics KK),to cure the coated layer to form a hard coat layer having a thickness of3 μm.

Then, the aforesaid coating solution A for a low-refractive-index layerwas coated onto the hard coat layer using a bar coater, and it was driedat 80° C. and heated at 120° C. for 10 minutes to effect thermalcrosslinking, to form a low-refractive-index layer having a thickness of0.096 μm.

Example 3

The aforesaid coating solution G for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co.,Ltd.) having a thickness of 80 μm, using a bar coater, and the resultantfilm was dried at 120° C. and then irradiated with UV-rays at anirradiation dose of 300 mJ/cm² and an illuminance of 400 mW/cm², using a160 W/cm air-cooled metal halide lamp (manufactured by Ai Graphics KK),to cure the coated layer to form a hard coat layer having a thickness of3 μm.

Then, the aforesaid coating solution A for a low-refractive-index layerwas coated onto the hard coat layer using a bar coater, and it was driedat 80° C. and heated at 120° C. for 10 minutes to effect thermalcrosslinking, to form a low-refractive-index layer having a thickness of0.096 μm.

(Evaluation of the Film having a High Transmittance and Matt Property)

As for the resultant films, the following items were evaluated:

(1) Total Light Transmittance and Haze

Total light transmittance and haze of the resultant films were measuredusing a haze meter MODEL 1001DP (trade name, manufactured by NihonDenshoku Kogyo KK).

(2) Evaluation of Pencil Hardness

Evaluation of pencil hardness disclosed in JIS K 5400 was carried out,as an index of scratch-resistance. After humidification of theanti-reflection film at temperature of 25° C. and humidity of 60% RH fortwo hours, scratch tests were carried out under the load condition of 1kg using test pencils of H and 2H grades, as defined in JIS S 6006.Then, evaluation was conducted according to the following criteria:

-   -   In the evaluation of n=5, no scratch was detected: ◯    -   In the evaluation of n=5, 1 or 2 scratch marks were detected: Δ    -   In the evaluation of n=5, at least 3 scratch marks were        detected: X        (3) Measurement of Kinetic Friction Coefficient

The kinetic friction coefficient was evaluated as an index ofsurface-sliding property. The resultant films each were adjusted inhumidity at 25° C. and a relative humidity of 60% for 2 hours, and thenwas carried out measurement by a HEIDON-14 kinetic friction tester,using a stainless steel ball having a diameter of 5 mmφ, under a load of100 g, at a velocity of 60 cm/min. The resultant measured value was usedas a kinetic friction coefficient.

(4) Evaluation of Matt Property

As an index of matt property, a 4×5 cm slide glass was placed on thematted layer of the thus-prepared film, and a weight of 1 kg wasoverlaid on the glass, to determine the state of non-uniformity in ringshape due to contact, according to the following evaluations. The mattproperty corresponds to the ability to prevent both unevenness indisplay and unevenness in brightness:

-   -   Non-uniformity was utterly not recognized: ◯    -   Slight non-uniformity was recognized in small areas: Δ    -   Generation of non-uniformity in all areas was recognized: X        (5) Refractive Index

The refractive index of the low-refractive-index layer after curing, wasdetermined by the following steps. Namely, on a polyethyleneterephthalate film exhibiting the refractive index of 1.66, thelow-refractive-index layer having a thickness of 0.1 μm was formed andcured according to the above-mentioned method. Then, a spectralreflectance of the resultant low-refractive-index layer at an incidenceof 5° in the range of 380 nm to 780 nm was measured by means of aspectrophotometer. The refractive index was determined by the minimumvalue of the obtained reflectance. In the Examples and the ComparativeExamples, each using a low-refractive-index layer, the refractive indexthereof was 1.42 or less respectively. This value was lower than therefractive index of the transparent support to be used.

The results which were obtained in these Examples and ComparativeExamples, are shown in Table 1.

The films in Examples 1 and 2 each exhibited the haze value of 1.0% ormore, but the total transmittance of light exceeding 93.5%. Further,each of them exhibited the pencil hardness of 2H or harder degree andcoefficient of kinetic friction of 0.10, and they were excellent in mattproperty.

With respect to Comparative Examples 1 and 2, in which the particleswere incorporated in the hard coat layer, matt property was improvedmuch more than that of Comparative Example 3 which was free of theparticles. However, as to the Comparative Examples 1 and 2, in which thelow-refractive-index layer was omitted, the total transmittance of lightwas as low as 92.4% and 92.1%, respectively.

With respect to Comparative Example 4, no matt property was obtained fornon-addition of the particles. Also with respect to Comparative Example5, the matt property was not enough because the particles used weresmall in particle diameter.

Example 3 was an example which used silica particles exhibiting a highMohs' scale of hardness. The film in Example 3 had the haze value ashigh as 5.8%, but exhibited the total transmittance of light of 93.5%which is a minimum goal. Further, the film had a pencil hardness of 2Hor more and a coefficient of kinetic friction of 0.10, and was excellentin matt property.

TABLE 1 Total light Pencil Haze transmittance hardness Kinetic frictionMatt (%) (%) H 2H coefficient (−) property Example 1 3.3 94.2 ◯ ◯ 0.10 ◯Example 2 1.8 93.8 ◯ ◯ 0.10 ◯ Comparative 1.2 92.4 ◯ ◯ 0.55 ◯ Example 1Comparative 3.8 92.1 ◯ ◯ 0.53 ◯ Example 2 Comparative 0.0 92.2 ◯ ◯ 0.57X Example 3 Comparative 0.0 94.0 ◯ ◯ 0.10 X Example 4 Comparative 1.894.0 ◯ ◯ 0.10 Δ Example 5 Example 3 5.8 93.5 ◯ ◯ 0.10 ◯

Example 4

The aforesaid coating solution A for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, trade name, manufactured by FujiPhoto Film Co., Ltd.) having a thickness of 80 μm, using a bar coater,and the resultant film was dried at 120° C. and then irradiated withUV-rays at an irradiation dose of 300 mJ/cm² and an illuminance of 400mW/cm², using a 160 W/cm air-cooled metal halide lamp (manufactured byAi Graphics KK), to cure the coated layer to form a hard coat layerhaving a thickness of 3 μm.

Then, the aforesaid coating solution A for a low-refractive-index layerwas coated onto the hard coat layer using a bar coater, and it was driedat 80° C. and heated at 120° C. for 10 minutes to effect thermalcrosslinking, to form a low-refractive-index layer having a thickness of0.096 μm.

Example 5

The aforesaid coating solution B for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co.,Ltd.) having a thickness of 80 μm, using a bar coater, and the resultantfilm was dried at 120° C. and then irradiated with UV-rays at anirradiation dose of 300 mJ/cm² and an illuminance of 400 mW/cm², using a160 W/cm air-cooled metal halide lamp (manufactured by Ai Graphics KK),to cure the coated layer to form a hard coat layer having a thickness of3 μm.

Then, the aforesaid coating solution A for a low-refractive-index layerwas coated onto the hard coat layer using a bar coater, and it was driedat 80° C. and heated at 120° C. for 10 minutes to effect thermalcrosslinking, to form a low-refractive-index layer having a thickness of0.096 μm.

Comparative Example 6

The aforesaid coating solution H for a hard coat layer was coated onto atriacetylcellulose film (TAC-TD80U, manufactured by Fuji Photo Film Co.,Ltd.) having a thickness of 80 μm, using a bar coater, and the resultantfilm was dried at 120° C. and then irradiated with UV-rays at anirradiation dose of 300 mJ/cm² and an illuminance of 400 mW/cm², using a160 W/cm air-cooled metal halide lamp (manufactured by Ai Graphics KK),to cure the coated layer to form a hard coat layer having a thickness of3 μm.

Then, the aforesaid coating solution A for a low-refractive-index layerwas coated onto the hard coat layer using a bar coater, and it was driedat 80° C. and heated at 120° C. for 10 minutes to effect thermalcrosslinking, to form a low-refractive-index layer having a thickness of0.096 μm.

(Evaluation of the Film having a High Transmittance and Matt Property)

As for the thus-prepared films, the following items were evaluated:

(1) Total light transmittance and haze

(2) Evaluation of pencil hardness

(3) Measurement of kinetic friction coefficient

(4) Evaluation of matt property

(5) Refractive Index

With regard to (1) to (5), tests and evaluation were carried out in thesame manner as mentioned above. The refractive index of thelow-refractive-index layer was 1.42.

(6) Evaluation of Scratch-Preventing Property

As an index of scratch-preventing property, the prepared film wasmounted onto a stainless steel panel having a size of 20×75 mm and aweight of 500 g so that the matted surface would become an external sidethereof. This panel was placed on a polyethylene terephthalate film soas to face the matted surface downward and then the stainless steelpanel was pushed and pulled at a rate of 20 mm/min. Scratch mark thusformed on the polyethylene terephthalate film was evaluated as follows:

-   -   No scratch was detected: ◯    -   Scratch was detected partially in the test area: Δ    -   Scratch was detected wholly in the test area: X

The results obtained are shown in Table 2.

Even though the films in Examples 4 and 5 each had the haze value of1.0% or more, they exhibited the total transmittance of light of morethan 93.5%. Further, they each had a pencil hardness of 2H or harder anda coefficient of kinetic friction of 0.10, and were excellent in bothmatt property and scratch resistance.

On the other hand, the film in Comparative Example 6 was inferior inscratch resistance because silica particles exhibiting a high Mohs'scale of hardness were used, and also the matt property was not enoughbecause the silica particles to be used were of small particle diameter.

TABLE 2 Total light Kinetic trans- Pencil friction Matt Scratch Hazemittance hardness coefficient pro- re- (%) (%) H 2H (−) perty sistanceExample 4 1.2 94.2 ◯ ◯ 0.10 ◯ ◯ Example 5 3.4 94.0 ◯ ◯ 0.10 ◯ ◯Comparative 1.8 94.0 ◯ ◯ 0.10 Δ X Example 6

Further, a polarizing plate having a high transmittance and mattproperty was prepared using the film of Example 5. Further, a liquidcrystal display device was produced, using the foregoing film, as a backlight side polarizing plate among two polarizing plates that weredisposed on both sides of a liquid crystal cell, the above-mentionedmatted layer being arranged toward the direction of the back light side.As a result, in the liquid crystal display device, the brightness in thewhite display increased by 2%, compared to that of the display devicewhich did not use the foregoing film. In the liquid crystal displaydevice of the invention, reduction in display quality due to theunevenness was not observed even after 7 days, in both environments of aroom temperature and a high temperature elevated to 60° C. Also in thefilms of Examples 3 and 4, the same results (properties) as above wereobtained. When the film of Comparative Example 1 was used, reduction indisplay quality due to the unevenness was not observed, but the devicefailed to improve brightness. When the films of Comparative Examples 4and 5 were used, the brightness increased by the range of 1 to 2% butthey failed to prevent the display quality from being deteriorated dueto the unevenness. Further, it is assumed that since the films ofExamples 1 and 2 also provided the similar results as those of Examples3 to 5 in the contact angle and glass contact tests, these films wouldalso exhibit the similar results as the above, in the mounting test.

INDUSTRIAL APPLICABILITY

The films having matt property of the present invention are of hightransmittance, and are able to prevent occurrence of unevenness inbrightness and unevenness in display due to thermal expansion of alight-tuning film that is used in a liquid crystal display device.Therefore, the films are preferable for use in the polarizing plate of aliquid crystal display device. Further, the films having a hightransmittance of the present invention are especially preferable for usein the polarizing plate of a liquid crystal display device, because thespecific low-refractive-index layer that would be provided in each ofthe film, provides an excellent scratch resistance in addition to theabove-mentioned characteristics, and the films do not cause a scratch ona light-tuning film.

Further, the polarizing plates having matt property of the presentinvention are preferable as a polarizing plate of a liquid crystaldisplay device, because they exhibit a high brightness and provide anexcellent scratch resistance in addition to the above-mentionedcharacteristics, and they do not cause a scratch on a light-tuning film.

Accordingly, the liquid crystal display device of the present inventionshows a suitable high display quality.

Having described our invention as related to the present embodiments, itis our intention that the invention not be limited by any of the detailsof the description, unless otherwise specified, but rather be construedbroadly within its spirit and scope as set out in the accompanyingclaims.

1. A film in a display device, having a high transmittance and mattproperty, comprising, on a transparent support, (a) a hard coat layercomprising a cross-linked binder polymer and particles incorporatedtherein, wherein the particles have a particle size of from 1.0 to 10 μmthat is larger than the thickness of the hard coat layer therebyproviding a concavo-convex structure, wherein said particles are set incontact with the transparent support, wherein a density of the particlesis in a range of from 100 to 5000 particles/m², and wherein theparticles are monodispersed transparent fine particles having a particlesize distribution of 0.2 or less in terms of coefficient of variation,and (b) a low-refractive-index layer having a refractive index of 1.45or less and a coefficient of kinetic friction of 0.2 or less, whereinthe low-refractive-index layer covers said hard coat layer so as tomaintain said concavo-convex structure formed by said particlesincorporated in the hard coat layer, and wherein saidlow-refractive-index layer comprises a fluorine-containingmacromolecular compound that is cross-linked by heat or ionizationradiation, wherein the film shows a haze value of 1.0% or more, and atotal transmittance of light of 93.5% or more, whereby occurrence ofnon-uniformity of brightness due to light interference is prevented byvirtue of the high transmittance and matt property of the film, when theconcavo-convex structure of a surface of the film is contacted with asmooth surface of a layer in a display device.
 2. The film in a displaydevice, having a high transmittance and matt property according to claim1, wherein the particles are monodispersed transparent fine particlesformed from a resin having a Moh's scale of hardness of less than
 7. 3.The film in a display device, having a high transmittance and mattproperty according to claim 1, wherein the particles are monodispersedtransparent fine particles formed from a resin having a Moh's scale ofhardness of less than 7, and wherein said low-refractive-index layer hasa coefficient of kinetic friction of 0.15 or less.
 4. The film in adisplay device, having a high transmittance and matt property accordingto claim 1, wherein an average particle diameter of the particles islarger than the thickness of the hard coat layer by 0.5 to 5.0 μm. 5.The film in a display device, having a high transmittance and mattproperty according to claim 1, wherein the density of the particles isin a range of 200 to 2000 particles/m².
 6. The film in a display device,having a high transmittance and matt property according to claim 1,wherein the low-refractive-index layer has a coefficient of kineticfriction of 0.15 or less.
 7. The film in a display device, having a hightransmittance and matt property according to claim 1, wherein said filmis provided on at least one side of a polarizing layer to form apolarizing plate of the display device, and wherein the concavo-convexstructure of a surface of the film is disposed at the side opposite tothe polarizing layer, whereby occurrence of non-uniformity of brightnessdue to light interference is prevented by virtue of the hightransmittance and matt property of the film, when the concavo-convexstructure of a surface of the polarizing plate is brought into contactwith a smooth surface of a layer of the display device.
 8. A polarizingplate in a display device, having a high transmittance and mattproperty, comprising a polarizing layer and two protective filmsthereon, wherein at least one of the protective films is a film having ahigh transmittance and matt property, wherein a matted layer is disposedat the opposite side to the polarizing layer, wherein: the film having ahigh transmittance and matt property comprises, on a transparentsupport, (a) a hard coat layer comprising a cross-linked binder polymerand particles incorporated therein, wherein the particles have aparticle size of from 1.0 to 10 μm that is larger than the thickness ofthe hard coat layer thereby providing a concavo-convex structure,wherein said particles are set in contact with the transparent support,wherein a density of the particles is in a range of from 100 to 5000particles/m², and wherein the particles are monodispersed transparentfine particles having a particle size distribution of 0.2 or less interms of coefficient of variation, and (b) a low-refractive-index layerhaving a refractive index of 1.45 or less and a coefficient of kineticfriction of 0.2 or less, wherein the low-refractive-index layer coverssaid hard coat layer so as to maintain said concavo-convex structureformed by said particles incorporated in the hard coat layer, andwherein said low-refractive-index layer comprises a fluorine-containingmacromolecular compound that is cross-linked by heat or ionizationradiation, wherein the film shows a haze value of 1.0% or more, and atotal transmittance of light of 93.5% or more, whereby occurrence ofnon-uniformity of brightness due to light interference is prevented byvirtue of the high transmittance and matt property of the film, when theconcavo-convex structure of a surface of the film is contacted with asmooth surface of a layer in a display device; or the film having a hightransmittance and matt property comprises, on a transparent support, (a)a hard coat layer comprising a cross-linked binder polymer and particlesincorporated therein, wherein the particles have a particle size of from1.0 to 10 μm that is larger than the thickness of the hard coat layerthereby providing a concavo-convex structure, wherein said particles areset in contact with the transparent support, wherein a density of theparticles is in a range of from 100 to 5000 particles/m², and whereinthe particles are monodispersed transparent fine particles having aparticle size distribution of 0.2 or less in terms of coefficient ofvariation, and (b) a low-refractive-index layer having a refractiveindex of 1.45 or less and a coefficient of kinetic friction of 0.2 orless, wherein the low-refractive-index layer covers said hard coat layerso as to maintain said concavo-convex structure formed by said particlesincorporated in the hard coat layer, and wherein saidlow-refractive-index layer comprises a fluorine-containingmacromolecular compound that is cross-linked by heat or ionizationradiation, wherein the film shows a haze value of 1.0% or more, and atotal transmittance of light of 93.5% or more, whereby occurrence ofnon-uniformity of brightness due to light interference is prevented byvirtue of the high transmittance and matt property of the film, when theconcavo-convex structure of a surface of the film is contacted with asmooth surface of a layer in a display device, wherein the particles aremonodispersed transparent fine particles formed from a resin having aMoh's scale of hardness of less than 7; or the film having a hightransmittance and matt property comprises on a transparent support, (a)a hard coat layer comprising a cross-linked binder polymer and particlesincorporated therein, wherein the particles have a particle size of from1.0 to 10 μm that is larger than the thickness of the hard coat layerthereby providing a concavo-convex structure, wherein said particles areset in contact with the transparent support, wherein a density of theparticles is in a range of from 100 to 5000 particles/m², and whereinthe particles are monodispersed transparent fine particles having aparticle size distribution of 0.2 or less in terms of coefficient ofvariation, and (b) a low-refractive-index layer having a refractiveindex of 1.45 or less and a coefficient of kinetic friction of 0.2 orless, wherein the low-refractive-index layer covers said hard coat layerso as to maintain said concavo-convex structure formed by said particlesincorporated in the hard coat layer, and wherein saidlow-refractive-index layer comprises a fluorine-containingmacromolecular compound that is cross-linked by heat or ionizationradiation, wherein the film shows a haze value of 1.0% or more, and atotal transmittance of light of 93.5% or more, whereby occurrence ofnon-uniformity of brightness due to light interference is prevented byvirtue of the high transmittance and matt property of the film, when theconcavo-convex structure of a surface of the film is contacted with asmooth surface of a layer in a display device, wherein the particles aremonodispersed transparent fine particles formed from a resin having aMoh's scale of hardness of less than 7, and wherein saidlow-refractive-index layer has a coefficient of kinetic friction of 0.15or less.
 9. A liquid crystal display device, comprising the film havinga high transmittance and matt property, wherein: the film having a hightransmittance and matt property comprises, on a transparent support, (a)a hard coat layer comprising a cross-linked binder polymer and particlesincorporated therein, wherein the particles have a particle size of from1.0 to 10 μm that is larger than the thickness of the hard coat layerthereby providing a concavo-convex structure, wherein said particles areset in contact with the transparent support, wherein a density of theparticles is in a range of from 100 to 5000 particles/m ², and whereinthe particles are monodispersed transparent fine particles having aparticle size distribution of 0.2 or less in terms of coefficient ofvariation, and (b) a low-refractive-index layer having a refractiveindex of 1.45 or less and a coefficient of kinetic friction of 0.2 orless, wherein the low-refractive-index layer covers said hard coat layerso as to maintain said concavo-convex structure formed by said particlesincorporated in the hard coat layer, and wherein saidlow-refractive-index layer comprises a fluorine-containingmacromolecular compound that is cross-linked by heat or ionizationradiation, wherein the film shows a haze value of 1.0% or more, and atotal transmittance of light of 93.5% or more, whereby occurrence ofnon-uniformity of brightness due to light interference is prevented byvirtue of the high transmittance and matt property of the film, when theconcavo-convex structure of a surface of the film is contacted with asmooth surface of a layer in a display device; or the film having a hightransmittance and matt property comprises, on a transparent support, (a)a hard coat layer comprising a cross-linked binder polymer and particlesincorporated therein, wherein the particles have a particle size of from1.0 to 10 μm that is larger than the thickness of the hard coat layerthereby providing a concavo-convex structure, wherein said particles areset in contact with the transparent support, wherein a density of theparticles is in a range of from 100 to 5000 particles/m², and whereinthe particles are monodispersed transparent fine particles having aparticle size distribution of 0.2 or less in terms of coefficient ofvariation, and (b) a low-refractive-index layer having a refractiveindex of 1.45 or less and a coefficient of kinetic friction of 0.2 orless, wherein the low-refractive-index layer covers said hard coat layerso as to maintain said concavo-convex structure formed by said particlesincorporated in the hard coat layer, and wherein saidlow-refractive-index layer comprises a fluorine-containingmacromolecular compound that is cross-linked by heat or ionizationradiation, wherein the film shows a haze value of 1.0% or more, and atotal transmittance of light of 93.5% or more, whereby occurrence ofnon-uniformity of brightness due to light interference is prevented byvirtue of the high transmittance and matt property of the film, when theconcavo-convex structure of a surface of the film is contacted with asmooth surface of a layer in a display device, wherein the particles aremonodispersed transparent fine particles formed from a resin having aMoh's scale of hardness of less than 7; or the film having a hightransmittance and matt property comprises, on a transparent support, (a)a hard coat layer comprising a cross-linked binder polymer and particlesincorporated therein, wherein the particles have a particle size of from1.0 to 10 μm that is larger than the thickness of the hard coat layerthereby providing a concavo-convex structure, wherein said particles areset in contact with the transparent support, wherein a density of theparticles is in a range of from 100 to 5000 particles/m², and whereinthe particles are monodispersed transparent fine particles having aparticle size distribution of 0.2 or less in terms of coefficient ofvariation, and (b) a low-refractive-index layer having a refractiveindex of 1.45 or less and a coefficient of kinetic friction of 0.2 orless, wherein the low-refractive-index layer covers said hard coat layerso as to maintain said concavo-convex structure formed by said particlesincorporated in the hard coat layer, and wherein saidlow-refractive-index layer comprises a fluorine-containingmacromolecular compound that is cross-linked by heat or ionizationradiation, wherein the film shows a haze value of 1.0% or more, and atotal transmittance of light of 93.5% or more, whereby occurrence ofnon-uniformity of brightness due to light interference is prevented byvirtue of the high transmittance and matt property of the film, when theconcavo-convex structure of a surface of the film is contacted with asmooth surface of a layer in a display device, wherein the particles aremonodispersed transparent fine particles formed from a resin having aMoh's scale of hardness of less than 7, and wherein saidlow-refractive-index layer has a coefficient of kinetic friction of 0.15or less.
 10. A liquid crystal display device, comprising two polarizingplates provided on both sides of a liquid crystal cell, wherein thepolarizing plate provided at the back light side is a polarizing platehaving a high transmittance and matt property, the matted layer beingdisposed toward the back light side, wherein the polarizing plate havinga high transmittance and matt property comprises a polarizing layer andtwo protective films thereon, wherein at least one of the protectivefilms is a film having a high transmittance and matt property, wherein amatted layer is disposed at the opposite side to the polarizing layer,wherein: the film having a high transmittance and matt propertycomprises, on a transparent support, (a) a hard coat layer comprising across-linked binder polymer and particles incorporated therein, whereinthe particles have a particle size of from 1.0 to 10 μm that is largerthan the thickness of the hard coat layer thereby providing aconcavo-convex structure, wherein said particles are set in contact withthe transparent support, wherein a density of the particles is in arange of from 100 to 5000 particles/m², and wherein the particles aremonodispersed transparent fine particles having a particle sizedistribution of 0.2 or less in terms of coefficient of variation, and(b) a low-refractive-index layer having a refractive index of 1.45 orless and a coefficient of kinetic friction of 0.2 or less, wherein thelow-refractive-index layer covers said hard coat layer so as to maintainsaid concavo-convex structure formed by said particles incorporated inthe hard coat layer, and wherein said low-refractive-index layercomprises a fluorine-containing macromolecular compound that iscross-linked by heat or ionization radiation, wherein the film shows ahaze value of 1.0% or more, and a total transmittance of light of 93.5%or more, whereby occurrence of non-uniformity of brightness due to lightinterference is prevented by virtue of the high transmittance and mattproperty of the film, when the concavo-convex structure of a surface ofthe film is contacted with a smooth surface of a layer in a displaydevice; or the film having a high transmittance and matt propertycomprises, on a transparent support, (a) a hard coat layer comprising across-linked binder polymer and particles incorporated therein, whereinthe particles have a particle size of from 1.0 to 10 μm that is largerthan the thickness of the hard coat layer thereby providing aconcavo-convex structure, wherein said particles are set in contact withthe transparent support, wherein a density of the particles is in arange of from 100 to 5000 particles/m², and wherein the particles aremonodispersed transparent fine particles having a particle sizedistribution of 0.2 or less in terms of coefficient of variation, and(b) a low-refractive-index layer having a refractive index of 1.45 orless and a coefficient of kinetic friction of 0.2 or less, wherein thelow-refractive-index layer covers said hard coat layer so as to maintainsaid concavo-convex structure formed by said particles incorporated inthe hard coat layer, and wherein said low-refractive-index layercomprises a fluorine-containing macromolecular compound that iscross-linked by heat or ionization radiation, wherein the film shows ahaze value of 1.0% or more, and a total transmittance of light of 93.5%or more, whereby occurrence of non-uniformity of brightness due to lightinterference is prevented by virtue of the high transmittance and mattproperty of the film, when the concavo-convex structure of a surface ofthe film is contacted with a smooth surface of a layer in a displaydevice, wherein the particles are monodispersed transparent fineparticles formed from a resin having a Moh's scale of hardness of lessthan 7; or the film having a high transmittance and matt propertycomprises, on a transparent support, (a) a hard coat layer comprising across-linked binder polymer and particles incorporated therein, whereinthe particles have a particle size of from 1.0 to 10 μm that is largerthan the thickness of the hard coat layer thereby providing aconcavo-convex structure, wherein said particles are set in contact withthe transparent support, wherein a density of the particles is in arange of from 100 to 5000 particles/m², and wherein the particles aremonodispersed transparent fine particles having a particle sizedistribution of 0.2 or less in terms of coefficient of variation, and(b) a low-refractive-index layer having a refractive index of 1.45 orless and a coefficient of kinetic friction of 0.2 or less, wherein thelow-refractive-index layer covers said hard coat layer so as to maintainsaid concavo-convex structure formed by said particles incorporated inthe hard coat layer, and wherein said low-refractive-index layercomprises a fluorine-containing macromolecular compound that iscross-linked by heat or ionization radiation, wherein the film shows ahaze value of 1.0% or more, and a total transmittance of light of 93.5%or more, whereby occurrence of non-uniformity of brightness due to lightinterference is prevented by virtue of the high transmittance and mattproperty of the film, when the concavo-convex structure of a surface ofthe film is contacted with a smooth surface of a layer in a displaydevice, wherein the particles are monodispersed transparent fineparticles formed from a resin having a Moh's scale of hardness of lessthan 7, and wherein said low-refractive-index layer has a coefficient ofkinetic friction of 0.15 or less.
 11. The film in a display device,having a high transmittance and matt property according to claim 1,wherein said film is provided on at least one side of a polarizing layerto form a polarizing plate of the display device, and wherein theconcavo-convex structure of a surface of the film is disposed at theside opposite to the polarizing layer, wherein said polarizing plate isarranged in the display device such that the concavo-convex structure isdisposed toward a back light side, and the polarizing plate is locatednext to a light tuning film layer, without being bonded to the lighttuning film layer, with a slight gap existing therebetween such that theconcavo-convex structure occasionally contacts a smooth surface of thelight tuning film layer during operation of the display device, wherebyoccurrence of non-uniformity of brightness due to light interference isprevented by virtue of the high transmittance and matter property of thefilm, when the concavo-convex structure of a surface of the polarizingplate is brought into contact with the smooth surface of the lighttuning film layer that is elongated by heating during operation of thedisplay device.